preparation and single enantiomers of chiral at metal bis ... · synthetic procedures and...

1

Supplementary information for

Preparation and single enantiomers of chiral at metal bis-

cyclometallated iridium complexes

David L. Davies,* Kuldip Singh, Shalini Singh and Barbara Villa Marcos

Department of Chemistry,

University of Leicester

Leicester LE1 7RH

Page

Synthetic procedures and characterisation for 1a,b, 2a,b and 3a including crystal data for-

1b and -2a

2-7

Fig. S1:Wireframe crystal structures showing key NOEs ofΛS-1a (left) and ∆S-1a (right). 8

Fig.S2: X-ray crystal structure of ΛS-1b. Selected bond lengths (Ǻ) and bond angles (°) 8

Fig.S3: X-ray crystal structure of ∆S-2a. Selected bond lengths (Ǻ) and bond angles (°) 9

Fig S4 CD spectra of ∆S-2a(D) and ΛS-2a (L) 9

Fig S5 1H NMR spectra of racemic, -4a and -4a 10

Fig S6 CD spectra of ∆-4a and Λ-4a 11

Fig S7a and S7b HPLC of racemic 4a and -4a 11-12

Fig S8 NMR spectra of product from reaction of ΔΔ-3a with (S)-Na(L1) showing ΔS-1a

formed in very high diasteroselectivity

13

Fig S9 NMR spectra of product from reaction of ΔΔ-3a with (S)-Na(L2) showing only ΔS-2a 13

Electronic Supplementary Material (ESI) for Chemical CommunicationsThis journal is © The Royal Society of Chemistry 2013

2

General information and materials

All reactions were carried out under an inert atmosphere of nitrogen and under microwave

irradiation unless stated otherwise. After work up all the complexes were air stable. Microwave

reactions were carried out in a CEM-Discover commercial microwave reactor. 1H, and 13C–{1H} NMR

spectra were obtained using a DRX 400 MHz spectrometer. Chemical shifts were recorded in ppm

(on δ scale with tetramethylsilane as internal reference), and coupling constants are reported in Hz.

FAB mass spectra were obtained on a Kratos concept mass spectrometer using NOBA as matrix. The

electrospray (ES) mass spectra were recorded using a micromass Quattra LC mass spectrometer in

HPLC grade acetonitrile except methanol for 2.6d. UV – Vis absorption measurements were carried

out on a Shimadzu UV – 1600 series spectrometer in dry DCM. Cyclic voltammetry measurements

were performed with an Eco Chemie Autolab using a one-compartment cell under N2 gas, equipped

with a Pt disc working electrode, a Pt gauze counter electrode and a silver wire reference electrode.

The supporting electrolyte was Et4NClO4 (0.1 mol L-1) in acetonitrile. Elemental analyses were

performed at London Metropolitan University. All starting materials were obtained from Aldrich or

Alfa Aesar.

General preparative procedure

The general procedure was as follows a mixture of the chiral ligand (X^Y = (S)-HL1, (S)-HL2), (2.2-2.4

equiv) and an equimolar amount of NaOMe in methanol (3 ml) was warmed gently at 40 C for 15

mins. A solution of the appropriate dimer [Ir(C^N)2Cl]2 1a,b (1 equiv) in DCM (6 ml) was added and

the mixture was stirred for 2-4 hrs at room temperature. After this time the solvent was removed in

vacuo and the residue was dissolved in DCM (15 ml) and passed through celite. The filtrate was

reduced in volume and hexane was added slowly to induce precipitation. The precipitate was

isolated, washed with hexane and dried in vacuo.

Synthesis of ∆S/ΛS-1a

This was prepared from [Ir(ppz)2Cl]2a (140 mg, 0.136 mmol), (S)-HL1 (61.3 mg, 0.299 mmol),

and NaOMe (16.2 mg, 0.299 mmol) and after work up gave ∆S/ΛS-

1a as a grey solid (combined yield 157 mg, 85%). Slow diffusion of

hexane into a DCM solution of 1a afforded selectively crystals of

the S isomer (63 mg, 34%), the S isomer (40 mg, 21%) was

obtained from the mother liquor, by recrystallisation from

methanol/diethylether .Anal.Calcd for C30H28IrN5O2: C, 52.77, H,

4.13, N, 10.26. Found (ΛS): C, 52.68, H, 4.12, N, 10.17%.


3

1H NMR (CDCl3) S: δ 8.05, 8.03 (2H, 2 X d, J = 2.7, He, e′), 7.63 (1H, d, J = 2.3, Hg′), 7.60 – 7.57 (2H, m,

H4, g), 7.17 – 7.09 (3H, m, H2, d, d′), 6.84 (1H, td, J = 7.4, 1.2, Hc), 6.80 (1H, td, J = 7.8, 1.2, Hc′), 6.67 (1H,

d, J = 7.8, H1), 6.64 – 6.58 (3H, m, Hb. b′, f′), 6.52 (1H, t, J = 2.7, Hf), 6.37 (1H, dd, J = 7.8, 1.6, Ha′), 6.33

(1H, ddd, J = 7.8, 6.7, 1.2, H3), 6.21 (1H, dd, J = 7.4, 1.2, Ha), 4.18 (1H, dd, J = 8.9, 3.9, H6), 3.76 (1H, t, J

= 8.9, H5), 3.04 (1H, ddd, J = 9.4, 3.5, 1.9, H7), 2.01 (1H, septd, J = 7.0, 1.9, H8), 0.89 (3H, d, J = 7.0,

MeA), 0.33 (3H, d, J = 7.0, MeB). 13C NMR: 169.82 (C9), 161.58 (C11), 144.06 (Ch), 143.87 (Ch′), 139.13

(Cg), 138.26 (Cg′), 135.89 (Ca′), 134.84 (Ci), 134.28 (Ca), 132.96 (C2), 130.23 (Ci′), 129.39 (C4), 125.77,

(Cb), 125.62 (Cb′), 125.23 (Ce, e′), 124.76 (C1), 121.52 (Cc), 120.78 (Cc′), 112.33 (C3), 110.59, 110.43 (Cd,

d′), 110.25 (C10), 107.07 (Cf′), 106.84 (Cf), 70.74 (C7), 66.41 (C5, 6), 28.89 (C8), 19.21 (MeB), 14.37 (MeA).

[α]D -593 in CHCl3.

1H NMR (CDCl3) S: δ 8.07 (1H, d, J = 2.9, He′), 7.99 (1H, d, J = 2.9, He),

7.80 (1H, d, J = 2.1, Hg′), 7.62 (1H, dd, J = 7.9, 1.8, H4), 7.43 (1H, d, J =

2.3, Hg), 7.15 – 7.09 (3H, m, H2, d, d′), 6.84 (1H, td, J = 7.6, 1.5, Hc), 6.80

(1H, td, J = 7.6, 1.5, Hc′), 6.73 – 6.67 (2H, m, H1, b), 6.63 (1H, t, J = 2.3,

Hf′), 6.61 (1H, td, J = 7.3, 1.2, Hb′), 6.52 (1H, t, J = 2.3, Hf), 6.34 (1H,

ddd, J = 7.8, 6.7, 0.8, H3), 6.29 (1H, dd, J = 7.6, 1.5, Ha′), 6.18 (1H, dd, J

= 7.6, 1.5, Ha), 4.29 – 4.18 (2H, m, H5, 6), 3.93 (1H, ddd, J = 8.8, 4.4, 3.2, H7), 0.53 (1H, septd, J = 7.0,

3.1, H8), 0.28 (3H, d, J = 7.0, MeB), 0.20 (3H, d, J = 6.7, MeA). 13C NMR: 170.08 (C9), 161.66 (C11),

144.60 (Ch′), 143.89 (Ch), 138.19 (Cg′), 137.01 (Cg), 135.14 (Ci), 134.25 (Ca′), 133.83 (Ca), 133.16 (C2),

129.95 (Ci′), 129.61 (C4), 125.78, 125.75 (C1, b′), 125.49 (Cb), 125.27 (Ce), 124.55 (Ce′), 121.55 (Cc),

120.91 (Cc′), 112.42 (C3), 110.54 (Cd), 110.36 (C10), 110.21 (Cd′), 107.04 (Cf′), 106.73 (Cf), 71.75 (C7),

66.51 (C5, 6), 28.42 (C8), 18.58 (MeB), 12.87 (MeA). [α]D +582 in CHCl3. MS (FAB): m/z 683 [M]+.

Synthesis of S/S-1b

This was prepared from [Ir(ppy)2Cl]2 b (70 mg, 0.065 mmol), (S)-HL1 (29.3 mg, 0.143 mmol),

and NaOMe (7.7 mg, 0.143 mmol) and after work up gave S/S-1b as a yellow solid (combined

yield 68 mg, 75%). Both isomers crystallised out together in

DCM/hexane or DCM/diethylether solvent mixtures but they could

be separated by hand picking due to significant variation in colour

and shape of the crystals. Anal.Calcd for C34H30IrN3O2.NaCl: C,

53.50, H, 3.96, N, 5.51. Found (S): C, 54.69, H, 3.35, N, 5.40%.

1H NMR (CDCl3) S: δ 8.87 (1H, ddd, J = 5.4, 1.6, 0.8, Hh′), 8.59 (1H,

ddd, J = 5.8, 1.6, 0.8, Hh), 7.85 – 7. 82 (2H, m, He, e′), 7.72 (1H, td, J =

7.4, 1.6, Hf′), 7.65 (1H, td, J = 7.4, 1.6, Hf), 7.58 – 7.53 (3H, m, H4, d, d′), 7.13 – 7.07 (2H, m, H2, g′), 6.92

Ir

NN

c

eg

NN

c'

e'

g'

a

b

a'

b'

d

d'

f'

i

i'

f

h'

h1

11

4

5

6

7

2

3

10

9

B

O

N

O

Me

Me

H HH

H

A

8


4

(1H, ddd, J = 7.4, 5.8, 1.6, Hg), 6.82 (1H, td, J = 7.8, 1.2, Hc), 6.79 (1H, td, J = 7.8, 1.2, Hc′), 6.70 (1H, td,

J = 7.4, 1.2, Hb), 6.66 – 6.62 (2H, m, H1, b′), 6.40 (1H, dd, J = 7.8, 1.2, Ha′), 6.34 (1H, ddd, J = 7.8, 6.7,

1.2, H3), 6.19 (1H, dd, J = 7.4, 1.2, Ha), 4.18 (1H, dd, J = 8.9, 3.5, H6), 3.65 (1H, t, J = 8.9, H5), 3.08 (1H,

ddd, J = 9.7, 3.9, 1.9, H7), 1.79 (1H, septd, J = 7.0, 1.9, H8), 0.84 (3H, d, J = 6.6, MeA), 0.20 (3H, d, J =

7.0, MeB). 13C NMR: 169.30 (Ck), 169.06 (C9), 168.23 (Ck′), 161.55 (C11), 152.54 (Ci), 155.33 (Ci′), 150.12

(Ch), 149.17 (Ch′), 144.64 (Cj), 144.05 (Cj′), 136.63 (Cf′), 136.36 (Cf), 134.20 (Ca′), 132.89 (C2), 132.21

(Ca), 129.48 (Cb), 129.07 (C4), 128.99 (Cb′), 125.18 (C1), 123.91, 123.80 (Cd, d′), 121.83 (Cg′), 121.04 (Cg),

120.91 (Cc), 120.14 (Cc′), 118.54, 117.88 (Ce, e′), 112.30 (C3), 110.51 (C10), 69.82 (C7), 66.86 (C5, 6), 28.85

(C8), 19.65 (MeA), 14.50 (MeB). [α]D -532 (for ∆S:ΛS 15:1) in DCM.

1H NMR (CDCl3) S: δ 9.02 (1H, ddd, J = 5.8, 1.6, 0.8, Hh′), 8.41

(1H, d, J = 5.8, Hh), 7.87 (1H, d, J = 8.2, He′), 7.80 (1H, d, J = 8.2,

He), 7.72 (1H, td, J = 8.2, 1.6, Hf′), 7.65 (1H, dd, J = 8.2, 1.9, H4),

7.63 (1H, td, J = 8.2, 1.6, Hf), 7.54 (1H, dd, J = 8.2, 1.2, Hd), 7.51

(1H, dd, J = 8.2, 1.6, Hd′), 7.14 – 7.09 (2H, m, H2, g′), 7.03 (1H,

ddd, J = 7.4, 5.9, 1.6, Hg), 6.83 (1H, td, J = 7.4, 1.2, Hc), 6.79 (1H,

td, J = 7.8, 0.8, Hc′), 6.75 (1H, td, J = 7.4, 1.6, Hb), 6.69 (1H, dd, J

= 8.6, 1.2, H1), 6.66 (1H, td, J = 7.4, 1.2, Hb′), 6.37 (1H, dd, J =

7.4, 1.2, Ha′), 6.34 (1H, ddd, J = 7.8, 6.7, 1.2, H3), 6.08 (1H, dd, J = 7.4, 1.2, Ha), 4.27 – 4.19 (2H, m, H5,

6), 3.95 (1H, ddd, J = 8.2, 4.7, 3.1, H7), 0.73 (1H, septd, J = 7.0, 3.1, H8), 0.24 (3H, d, J = 7.0, MeB), 0.06

(3H, d, J = 7.0, MeA). 13C NMR: 169.28 (Ck), 169.19 (C9), 168.62 (Ck′), 161.67 (C11), 153.39 (Ci), 148.86

(Ch′), 148.72 (Ci′), 147.73 (Ch), 145.11 (Cj′), 144.48 (Cj), 136.63 (Cf′), 136.56 (Cf), 133.31 (C2), 132.45

(Ca′), 131.35 (Ca), 129.78 (C4), 129.37 (Cb, b′), 124.79 (C1), 123.84, 123.77 (Cd, d′), 121.68 (Cg), 121.63

(Cg′), 121.19 (Cc), 120.28 (Cc′), 119.03 (Ce), 118.18 (Ce′), 112.68 (C3), 109.98 (C10), 72.04 (C7), 66.77 (C5,

6), 28.82 (C8), 18.58 (MeB), 12.75 (MeA). [α]D +570 in DCM. MS (FAB): m/z 706 [M+H]+.

Crystal data for -1b: C34H30IrN3O2•CHCl3, M = 824.18, orthorhombic, a = 9.355(5) Å, b = 14.083(8) Å,

c = 24.255(13) Å, α = 90.00°, β = 90.00°, γ = 90.00°, V = 3196(3) Å3, T = 150(2) K, space group

P2(1)2(1)2(1), Z = 4, 26714 reflections measured, 6950 independent reflections (Rint = 0.0665). The

final R1 values were 0.0348 (I> 2σ(I)). The final wR(F2) values were 0.0676 (I> 2σ(I)). The final R1

values were 0.0390 (all data). The final wR(F2) values were 0.0688 (all data). Flack parameter = -

0.003(7).


5

Synthesis of ∆S/ΛS-2a

This was prepared from [Ir(ppz)2Cl]2 a (70 mg, 0.068 mmol), (S)-HL2 (36.8 mg, 0.164 mmol),

and NaOMe (8.8 mg, 0.164 mmol) and after work up gave S/S-2a as a yellow solid (combined

yield 71 mg, 75%). ∆Sisomer was selectively crystallised from methanol, hence, the two isomers

were separated via fractional crystallisation from methanol until a ratio of 1:10 was attained for

S:S. Anal. Calcd for C33H28IrN5O: C, 56.39, H, 4.02, N, 9.96. Found (S): C, 56.28, H, 3.98, N, 9.87%.

1H NMR (CDCl3)S: δ 8.06 (1H, s, H5), 8.02 (1H, d, J = 3.1, He), 7.66 (1H,

d, J = 3.5, He′), 7.65 (1H, d, J = 2.3, Hg′), 7.52 (1H, d, J = 2.3, Hg), 7.19

(1H, ddd, J = 8.6, 6.7, 1.6, H2), 7.12 (1H, d, J = 7.4, Hd), 7.05 (1H, dd, J =

7.8, 1.6, H4), 7.01 – 6.92 (3H, m, H9, 9′, 10), 6.82 (1H, td, J = 7.4, 0.8, Hc),

6.77 (1H, dd, J = 7.8, 1.2, Hd′), 6.73 – 6.66 (3H, m, H1, b, c′), 6.61 (1H, td,

J = 7.8, 1.6, Hb′), 6.53 (1H, t, J = 2.7, Hf), 6.49 (1H, t, J = 2.7, Hf′), 6.39 –

6.34 (3H, m, H3, 8, 8′), 6.27 (1H, dd, J = 7.4, 1.2, Ha′), 6.13 (1H, dd, J =

7.4, 1.2, Ha), 4.94 (1H, q, J = 7.0, H6), 1.51 (3H, d, J = 7.0, Me). 13C NMR: 166.41 (C11), 161.08 (C5),

144.24 (Ch′), 143.88 (Ch), 141.99 (C7), 137.87 (Cg′), 137.81 (Cg), 135.21 (C4), 134.63 (Ci), 134.39 (Ca′),

134.17 (Ca), 133.70 (C2), 131.10 (Ci′), 127.92 (C9, 9′), 126.19 (C10), 125.96 (C8, 8′), 125.85 (Ce), 125.63

(Cb), 125.43 (Cb′), 125.23 (Ce′), 123.71 (C1), 121.68 (Cc), 121.42 (C12), 120.75 (Cc′), 112.89 (C3), 110.54

(Cd), 110.47 (Cd′), 106.87 (Cf), 106.71 (Cf′), 66.97 (C6), 22.81 (Me). [α]D -631 in CHCl3.

1H NMR (CDCl3) S: δ 8.11 (1H, d, J = 2.7, He′), 7.97 (1H, d, J = 2.7, He),

7.96 (1H, s, H5), 7.83 (1H, d, J = 2.3, Hg′), 7.36 – 7.22 (5H, m, H8, 8′, 9, 9′,

10), 7.20 (1H, dd, J = 7.8, 0.8, Hd′), 7.18 (1H, d, J = 2.3, Hg), 7.14 – 7.10

(2H, m, H2, d), 6.89 (1H, dd, J = 7.8, 1.9, H4), 6.87 – 6.81 (2H, m, Hc, c′),

6.72 – 6.68 (2H, m, Hb, b′), 6.67 (1H, t, J = 2.3, Hf′), 6.61 (1H, d, J = 8.2,

H1), 6.42 (1H, dd, J = 7.4, 1.6, Ha′), 6.38 (1H, t, J = 2.3, Hf), 6.30 (1H,

ddd, J = 7.8, 6.7, 1.2, H3), 6.22 (1H, dd, J = 7.4, 1.6, Ha), 4.80 (1H, q, J =

7.0, H6), 0.82 (3H, d, J = 7.0, Me). 13C NMR: 166.69 (C11), 162.25 (C5), 144.31 (Ch′), 143.93 (Ch), 142.04

(C7), 138.78 (Cg), 138.27 (Cg′), 135.21 (Ca′), 134.88 (C4), 134.27 (Ci), 134.17 (Ca), 133.58 (C2), 132.03

(Ci′), 128.60 (C9, 9′), 127.97 (C8, 8′), 127.56 (C10), 125.93 (Ce), 125.61 (Cb, b′), 125.45 (Ce′), 123.66 (C1),

121.97 (C12), 121.72 (Cc), 121.06 (Cc′), 112.76 (C3), 110.66 (Cd′), 110.47 (Cd), 107.16 (Cf′), 106.61 (Cf),

64.93 (C6), 20.33 (Me). [α]D +480 (for ∆S:ΛS 1:10) in CHCl3. MS (FAB): m/z 703 [M]+.

Crystal data for -2a: C33H28IrN5O•CH3OH, M = 734.85, orthorhombic, a = 8.794(4) Å, b = 11.361(5) Å,

c = 29.429(12) Å, α = 90.00°, β = 90.00°, γ = 90.00°, V = 2940(2) Å3, T = 150(2) K, space group

P2(1)2(1)2(1), Z = 4, 23226 reflections measured, 5780 independent reflections (Rint = 0.1160). The

Ir

NN

c

e

g

NN

c'

e'

g'

a

b

a'

b'

d

d'

f'

i

i'

f

h'

h

1 2

3

4

5

O

N

H Me6

7

9'

8

8'

10

9

12

11

1 2

3

4

5

O

N

H Me6

7

9'

8

8'9

12

11

10

c'

c a

b

a'

b'

d'

d

i'

ih

h'Ir

NN

NN

g'

f'

e'

e

g

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6

final R1 values were 0.0457 (I>2σ(I)). The final wR(F2) values were 0.0660 (I> 2σ(I)). The final R1 values

were 0.0602 (all data). The final wR(F2) values were 0.0696 (all data). Flack parameter = 0.005(10).

Synthesis of S/S-2b

This was prepared from [Ir(ppy)2Cl]2 b (70 mg, 0.065 mmol), (S)-HL2 (35.1 mg, 0.156 mmol),

and NaOMe (8.4 mg, 0.156 mmol) and after work up gave S/S-2bas a yellow solid (combined yield

74 mg, 79%). Both isomers crystallised out together in methanol but they could be separated by

hand picking due to significant variation in colour and shape of the crystals. Anal.Calcd for

C37H30IrN3O: C, 61.27, H, 4.17, N, 5.80. Found (S): C, 61.37, H, 4.23, N, 5.83%.

1H NMR (CDCl3) S: δ 8.90 (1H, dt, J = 5.5, 1.2, Hh′), 8.53 (1H, d, J =

5.5, Hh), 8.03 (1H, s, H5), 7.83 (1H, d, J = 8.2, He), 7.65 (1H, td, J =

7.4, 1.6, Hf), 7.62 – 7.59 (2H, m, He′, f′), 7.53 (1H, dd, J = 7.8, 1.2, Hd),

7.39 (1H, dd, J = 7.8, 1.2, Hd′), 7.12 (1H, ddd, J = 8.2, 7.1, 1.2, H2),

7.10 (1H, ddd, J = 8.6, 5.8, 2.7, Hg′), 7.02 – 6.91 (5H, m, H4, 9, 9′, 10, g),

6.81 (1H, td, J = 7.4, 1.2, Hc), 6.78 (1H, td, J = 7.8, 1.2, Hc′), 6.72 –

6.66 (2H, m, Hb, b′), 6.60 (1H, d, J = 7.8, H1), 6.42 (1H, dd, J = 7.4, 0.8,

Ha′), 6.35 – 6.31 (3H, m, H3, 8, 8′), 6.13 (1H, dd, J = 7.4, 0.8, Ha), 4.70 (1H, q, J = 7.0, H6), 1.45 (3H, d, J =

7.0, Me). 13C NMR: 169.08 (Ck), 168.34 (Ck′), 166.17 (C11), 161.13 (C5), 153.09 (Ci), 150.93 (Ci′), 148.95

(Ch), 148.58 (Ch′), 144.73 (Cj′), 144.46 (Cj), 142.12 (C7), 136.50 (Cf), 136.46 (Cf′), 134.96 (C4), 133.56

(C2), 133.13 (Ca′), 131.91 (Ca), 129.27 (Cb, b′), 127.90 (C9, 9′), 126.79 (C8, 8′), 126.63 (C10), 124.40 (C1),

124.16 (Cd′), 123.63 (Cd), 121.50 (C12), 121.45 (Cg′), 121.33 (Cg), 121.14 (Cc), 120.12 (Cc′), 118.87 (Ce),

118.25 (Ce′), 112.83 (C3), 65.84 (C6), 22.15 (Me). [α]D -535 in DCM.

1H NMR (CDCl3) S: δ 9.02 (1H, ddd, J = 5.8, 1.4, 0.8, Hh′), 8.19

(1H, ddd, J = 5.8, 1.4, 0.8, Hh), 8.11 (1H, s, H5), 7.93 (1H, d, J = 8.2,

He′), 7.80 – 7.75 (2H, m, He, f′), 7.63 (1H, dd, J = 7.6, 1.2, Hd′), 7.60 –

7.52 (2H, m, Hd, f), 7.35 – 7.27 (3H, m, H9, 9′, 10), 7.22 – 7.11 (3H, m,

H2, 8, 8′, g′), 6.92 (1H, dd, J = 7.8, 1.8, H4), 6.86 – 6.81 (2H, m, Hc, c′),

6.78 – 6.69 (3H, m, Hb, b′, g), 6.58 (1H, d, J = 8.5, H1), 6.47 (1H, dd, J

= 7.6, 1.2, Ha′), 6.30 (1H, ddd, J = 8.2, 6.7, 0.8, H3), 6.22 (1H, dd, J =

7.6, 1.2, Ha), 4.73 (1H, q, J = 7.0, H6), 0.73 (3H, d, J = 7.0, Me). 13C

NMR: 169.79 (Ck, k′), 167.13 (C11), 163.03 (C5), 154.10 (Ci), 152.97 (Ci′), 151.35 (Ch), 150.09 (Ch′),

146.45, 146.35 (Cj, j′), 143.22 (C7), 138.58 (Cf′), 138.11 (Cf), 136.56 (C4), 135.02 (C2), 134.77 (Ca′),

133.29 (Ca), 131.01 (Cb′), 130.18 (Cb), 129.91 (C9, 9′), 129.43 (C8, 8′), 129.08 (C10), 125.90 (Cd′), 125.14


7

(Cd), 124.69 (C1), 123.40 (Cg′), 123.18 (C12), 122.77 (Cg), 122.56, 121.90 (Cc, c′), 120.27 (Ce), 119.82 (Ce′),

114.18 (C3), 65.71 (C6), 22.49 (Me). [α]D +654 in DCM. MS (FAB): m/z 725 [M]+.

Synthesis of ∆∆-3a

TFA (162 mg, 109.7 µL, 1.423 mmol) was added to a solution

of ∆S-2a (50 mg, 0.071 mmol) in DCM (2 ml). H2O (2 ml) was added

to this reaction mixture after stirring it for an hour. The deep yellow

colour changed successively to pale yellow and colourless after

stirring for 48 hrs at room temperature. After this time, the aqueous

layer was separated and the organic layer was passed through celite. The filtrate was reduced in

volume and hexane was added slowly to induce precipitation. The precipitate was isolated, washed

with hexane and dried in vacuo to give ∆∆-3a as a grey solid (34 mg, 81%).1H NMR (CDCl3): δ 8.10

(4H, d, J = 2.3, He), 7.88 (4H, d, J = 2.0, Hg), 7.13 (4H, dd, J = 7.8, 1.2, Hd), 6.85 (4H, td, J = 7.4, 1.2, Hc),

6.75 (4H, t, J = 2.7, Hf), 6.63 (4H, td, J = 7.4, 1.2, Hb), 6.10 (4H, dd, J = 7.8, 1.2, Ha). MS (FAB): m/z 1071

[M-CF3CO2]+. MS (ES): m/z 561 [Ir(ppz)2(MeCN)2]

+.

Synthesis of ∆-4a

TFA (40.5 mg, 27.4 µL, 0.356 mmol) was added to a solution of ∆S-

2a (50 mg, 0.071 mmol) and bipy (12.2 mg, 0.078 mmol) in DCM (2 ml).

The reaction mixture was stirred for an hour and after that the reaction

mixture was washed with water (3 × 5 ml). The organic layer was

separated and washed and dried with anhydrous MgSO4. The volume of

filtrate was reduced and hexane was added slowly to induce precipitation. The precipitate was

isolated, washed with hexane and dried in vacuo to give ∆-4a as a yellow solid (38 mg, 72%). Using a

similar procedure Λ-4a was synthesised from ΛS-1a via ΛΛ-3a. 1H NMR (CD2Cl2): δ 9.23 (2H, d, J =

8.2, H4), 8.23 (2H, td, J = 8.2, 0.8, H3), 8.11 (2H, d, J = 2.7, He), 8.07 (2H, dd, J = 5.4, 1.2, H1), 7.40 (2H,

dd, J = 7.0, 5.8, H2), 7.29 (2H, dd, J = 7.8, 0.8, Hd), 7.05 (2H, td, J = 7.8, 1.2, Hc), 6.87 (2H, td, J = 7.4,

1.2, Hb), 6.84 (2H, d, J = 2.0, Hg), 6.54 (2H, t, J = 2.7, Hf), 6.31 (2H, dd, J = 7.4, 1.2, Ha). [α]D -471 for ∆-

4a and +473 for Λ-4a in DCM. MS (FAB): m/z 635 [M]+. rotation,-471 in DCM.

Measurement of enantiopurity by 1H NMR

A sample of 4a (3.74 mg, 5 × 10-3 mmol) was dissolved in 0.5 mL of CD2Cl2. 1 equiv. of Δ-

[Bu4N][trisphat] (5.06 mg, 5 × 10-3 mmol) was then added [in small portions].


8

Fig. S1:Wireframe crystal structures showing key NOEs ofΛS-1a (left) and ∆S-1a (right). Phenyl ring

with primes is trans to O while with non-primes is trans to imine N for both the isomers.

Fig.S2: X-ray crystal structure of ΛS-1b. Selected bond lengths (Ǻ) and bond angles (°): Ir(1)N(1),

2.033(4); Ir(1)N(2),2.042(5); Ir(1)N(3), 2.142(5); Ir(1)O(1), 2.123(4); Ir(1)C(11), 1.994(5);

Ir(1)C(22), 2.002(5); N(1)Ir(1)N(2), 172.84(18); N(1)Ir(1)C(11), 80.4(2);

N(2)Ir(1)C(22), 80.5(2); N(3)Ir(1)O(1), 85.98(17).

a b


9

Fig.S3: X-ray crystal structure of ∆S-2a. Selected bond lengths (Ǻ) and bond angles (°): Ir(1)N(1),

1.997(6); Ir(1)N(3),2.012(6); Ir(1)N(5), 2.139(7); Ir(1)O(1), 2.120(5); Ir(1)C(9), 2.000(8);

Ir(1)C(18), 2.001(8); N(1)Ir(1)N(3), 173.5(3); N(1)Ir(1)C(9), 80.4(3); N(3)Ir(1)C(18),

79.8(3); N(5)Ir(1)O(1), 88.6(3).

Fig S4 CD spectra of ∆S-2b and ΛS-2b

-80

-60

-40

-20

0

20

40

60

80

100

230 280 330 380 430 480 530


10

Figure S5


11

Fig S6 CD spectra of ∆S and ΛS-4a

CHIRALPAK® AD-H (250mmL x 4.6 ID) / 5μm Eluent: n-Heptane / EtOH / TEA / TFA 90:10:0.3:0.1 Flow Rate: 1.0mL/min Temperature: 25°C Detection: UV 250 nm

Fig S7a


12

Fig S7b


13

As mentioned in the paper to check the enantiopurity of -3a it was reacted separately with L1 and

L2. In each case this gave only 1 diastereomer. Relevant parts of the NMR spectra are shown below.

Figure S8: (a) Selected part of the crude 1H NMR spectrum of the reaction of ΔΔ-3a with (S)-Na(L1). ΔS-1a:ΛS-1a ratio is 53:1; (b) Selected part of the crude NMR spectrum of the 50:50 mixture of ΔS-1a:ΛS-1a formed from the reaction of racemic [Ir(ppz)2Cl]2 with (S)-Na(L1).

Figure S9: (a) Selected part of the crude 1H NMR spectrum of the reaction of ΔΔ-3a with (S)-

Na(L2). Only ΔS-2a is observed ; (b) Selected part of the crude NMR spectrum of the 50:50

mixture of ΔS-1a:ΛS-1a formed from the reaction of racemic [Ir(ppz)2Cl]2 with (S)-Na(L2).


preparation and single enantiomers of chiral at metal bis ... · synthetic procedures and...

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